C.sub.4 and higher olefins serve as a basic feedstock in the chemical industry for the synthesis of many important products, including, for instance, solvents, lubricants, detergents, and polymers. In each case, the reactivity of an olefin starting material for such a synthesis and/or the properties and performance of the resulting product may be strongly influenced by the particular structure, or mixture of structures, represented in the olefin. Thus, for example, detergents derived from linear olefins are as a rule substantially more biodegradable than corresponding detergents derived from olefins having multiple branches in their carbon structure, and the properties of polymers prepared from olefins are often greatly influenced by the position (alpha- or internal) of the double bond.
It is, in many cases, desirable to tailor the structure and/or the double bond position in a given olefin, to optimize its utility for conversion to products of interest. This is particularly true in various processes for the preparation of olefins having internal, rather than alpha, double bond position. The desired skeletal structure (commonly, but not exclusively, a linear structure) is typically obtained in an oligomerization process in which one or a mixture of lower carbon number olefins is converted into higher carbon number olefins. Of particular commercial importance is the oligomerization of ethylene to prepare higher carbon number, predominantly linear, alpha-olefins. Linear internal olefins are then prepared by double bond isomerization of the linear alpha-olefins.
Isomerization of higher carbon number alpha-olefins to internal olefins finds particular application in the process for the preparation of higher olefins from ethylene which is described in U.S. Pat. No. 3,647,906.